Until now, elevators in a building could not be used in case of fire. Generally, in many existing buildings, in case of fire, all elevators are recalled to a designated floor and can only be used by firefighters. Occupants need exit via stairs only. Signage and Fire alarm voice messages are issued accordingly. Because of the 9/11 event in New York, new codes and guidelines were developed which allow evacuation using elevators if a building infrastructure complies with specific rules. Such an Occupant Evacuation Operation (OEO) is for example defined in relevant codes for OEO, such as National Elevator Code ASME 17.1/CSA B44, Fire Alarm Codes NFPA 72 and others (US Building & Fire Codes, Local Codes, etc). Other countries may have different regulations.
The new US standards and regulations for the Occupant Evacuation Operation (OEO) require that the fire detection system evaluates when a specific level of a building is in an OEO relevant alarm status and when in evacuation status. This information shall be provided to the elevator system which may comprise multiple elevator banks and associated elevator controls. Furthermore, a close coordination between the voice evacuation messages and all the information displayed by the elevator system is absolutely required.
Conventional OEO implementations often require one or more control units which may be placed on each floor of a building or may control multiple floors and being connected with an elevator system which increases the cable connections significantly and thereby also increases system failures due to connection problems. At least one problem of such conventional systems is that they require many complex, manually configured generic control functions which are likely to be outdated and therefore need to be changed when something in the building changes. Those manually configurable generic control functions may comprise logic combinations of all relevant states with Boolean functions etc. These controls then activate hard-wired outputs which are connected to the elevator system.
Due to the complexity of such systems, in particular for multi-floor buildings, such as, e.g., skyscrapers, configuration and expansion of such systems is not easy. In particular, changes in regulation may require a reconfiguration of such a system that may not be easily achievable and require hardware changes or substitutions. Moreover, different countries may have different regulations and requirements for handling emergency situations in a building and associated OEOs. Thus, different customized systems may be necessary to comply with different regulation. Most importantly, changes in the usage of rooms/building parts and constructional changes may occur. It remains very difficult to adapt conventional systems to such changes.